FDA approval of a Humanitarian Device Exemption (HDE) application is necessary in order to allow the marketed use of a Humanitarian Use Device (HUD). The HDE is similar to a Pre-Market Approval (PMA), but because a HUD is exempt from the effectiveness requirements of a PMA, an HDE application is not required to contain the results of scientifically valid clinical investigations demonstrating that the device is effective for its intended purpose. The HDE must contain sufficient information for FDA to determine that the probable benefit to health outweighs the risk of injury or illness, taking into account the probable risks and benefits of currently available devices or alternative forms of treatment.